1. Field of the Invention
The present invention relates generally to a capsule filling apparatus, and more particularly to an apparatus for filling rigid capsules made of gelatin with tablets of the same cylindroidal shape as the capsule, wherein the capsules were held in an upright posture with the openings upward.
2. Description of the Prior Art
It is common practice to fill a rigid capsule made of gelatin with a fluid substance such as granular, powder or liquid medicine. Sometimes, such capsules are also filled with solid tablets, and in recent years, with tablets having the same cylindroidal shape as the capsule itself. Being covered with the capsule in this way, the tablet can be protected from damage or deformation. This is also advantageous in eliminating the necessity of putting identification marks or coloring directly upon the tablets but only putting it on the capsules themselves.
Japanese Laid-Open Patent Publication No. 52-39494 discloses an apparatus for filling a capsule with a disk-shaped tablet. In this capsule filling apparatus, a disk-shaped tablet fed into a chute is passed into a hole extending through a slider. The slider is then moved in the horizontal direction so as to send the tablet held inside the hole through a hole in a shutter into a capsule. The filling of the capsule is detected by the displacement of a detecting rod to be inserted in the capsule.
When a capsule is filled with a tablet having the same shape as the capsule, the tablet must be inserted upright into the capsule which is also held upright. It is difficult, however, to form a sequence of upright cylindroidal tablets in a vertical line. Tablets may not be fed continuously into capsules through the hole in the slider, thereby resulting in the failure of filling the capsules with them. The problem of empty capsules sometimes occurs. To solve this problem, care must be taken to maintain the supply of tablets into capsules.
The above-mentioned capsule filling apparatus employs a detecting rod which is inserted into a capsule after the capsule is filled with a tablet. The filling of the tablet is detected by the displacement of the detecting rod. In this arrangement, however, the detecting rod touches the tablet and may damage it. Moreover, ingredients of the tablet may stick to the tip of the detecting rod, which must be cleaned before a different kind of tablet is charged in the capsule.
Furthermore, when the capsule is filled with a capsule-shaped tablet, the upright tablet may not completely fit into the hole of the slider, and is likely to be suspended between the chute and the slider. When the slider is moved under this condition, the tablet may be cut off by a shearing force applied between the hole of the slider and the chute.